JP3025418B2 - Power transmission belt and method of manufacturing the same - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a power transmission belt and a method of manufacturing the same, and more particularly, to a countermeasure for abnormal vibration and abnormal noise when the power transmission belt is used on a back.

[0002]

2. Description of the Related Art In a power transmission belt in which a back canvas is adhered to an upper surface of an adhesive rubber layer, the back canvas is generally formed in a tubular shape by lap splicing in which both ends of a band-shaped fabric are vertically overlapped. , A step is generated at the overlapping portion. When the transmission belt is formed by using the rear canvas having the step as described above, as shown in FIG. 7, the adhesive rubber sheet c and the core c are sequentially placed on the rear canvas b externally fitted to the forming drum a. Line d, sheet e for adhesive rubber, sheet f for rib rubber
Is wound, the core wire d is displaced in the vertical direction corresponding to the step at the lap joint portion h of the back canvas b, and the core wire d is shifted from a normal position in the vulcanized transmission belt. It is embedded in the adhesive rubber layer in a state where it is in a state of being placed. When such a power transmission belt is used on a pulley by hanging it on the rear side, the power transmission belt runs unnaturally, and there is a problem that the power transmission belt abnormally vibrates or generates abnormal noise when the stepped portion passes through the pulley. Was. FIG. 7 shows a case in which the transmission belt is a V-ribbed belt. In FIG. 7, i is a sleeve made of an elastic body such as rubber, and a concave portion j and a convex portion k for forming a rib are formed on the inner peripheral surface thereof. Is formed.

Therefore, as disclosed in, for example, Japanese Patent Application Laid-Open No. Hei 4-151048, by joining two ends of a belt-like cloth constituting a rear canvas in abutting manner, a rear canvas causing a displacement of a core wire can be obtained. There has been proposed a transmission belt and a method of manufacturing the transmission belt in which the vertical overlap of the transmission belt is eliminated so that a step is not generated at a joint portion, and abnormal vibration and abnormal noise of the transmission belt are prevented.

[0004]

However, even if a step is eliminated at the joint portion of the back canvas by butt joining as in the above proposed example, the sheet for the adhesive rubber to be wound thereon upon molding is the conventional example. As shown in FIG. 8, a core wire d is formed by joining the adhesive rubber sheet e at the time of molding, as shown in FIG. At the point m, the core is displaced in the vertical direction corresponding to the level difference, and the core wire d is shifted from the normal position in the vulcanized power transmission belt as in the case of the latter (proposed example) of the conventional example. As a result, the transmission belt is abnormally vibrated or generates abnormal noise when used on the rear side.
The butted joints of the rear canvas b are denoted by reference numeral n. 8, the same portions as those shown in FIG. 7 are denoted by the same reference numerals.

[0005] Although the rear canvas is butt-joined as described above, the rear canvas is thin, and it is very difficult and inefficient as compared with the case where the thick canvas is butt-joined. Therefore, it is considered that the fact that the back canvas is generally joined by lap splicing has been conventionally performed.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and an object of the present invention is not to butt-join a thin back canvas alone but to butt-join it together with an adhesive rubber sheet as a thick material. By doing so, the vertical displacement of the core wire due to the overlap (step) of each end of the back canvas and the adhesive rubber sheet is eliminated, and the core wire is formed on the vulcanized power transmission belt by the regular bonding rubber layer. The belt is buried in a position to smoothly drive the belt when used on the back side, and to eliminate abnormal vibration and abnormal noise of the transmission belt. Another object of the present invention is to easily obtain a transmission belt free of abnormal vibration and abnormal noise by easily performing butt joining of the rear canvas.

[0007]

To achieve the above object, according to an aspect of the present invention comprises an adhesive rubber layer core wires are embedded in the belt longitudinal direction, top fabric is deposited on the upper surface of the adhesive rubber layer The following solutions were taken for the transmission belt and its manufacturing method.

More specifically, the first to third solutions of the present invention relate to a power transmission belt, and the first solution is to form the upper rubber portion of the adhesive rubber layer with the back canvas bounded by the cord. laminating a strip integral with the adhesion rubber sheet made of unvulcanized rubber sheet, on the state of the strip laminate
Serial both longitudinal ends with adhesive rubber sheet top fabric top and an adhesive rubber sheet lower surface abutting each other so as not to cause a step joined to a tubular, match-the said core wire
Winding on a cylindrical laminate formed into a cylindrical shape
The lower rubber part of the adhesive rubber layer
Cover with adhesive rubber sheet consisting of vulcanized rubber sheet
It is characterized by being embedded in an adhesive rubber layer .

According to a second aspect of the present invention, in the first aspect, the butt-joining of the band-shaped laminate is performed by sewing.

According to a third aspect of the present invention, in the first aspect, the butt-joining of the band-shaped laminate is performed by welding.

[0011] The fourth to sixth solutions of the present invention relate to a method of manufacturing a power transmission belt.
As a premise, a band-like laminate is prepared in which an adhesive rubber sheet made of an unvulcanized rubber sheet constituting an upper rubber portion of an adhesive rubber layer with the above-mentioned cord being integrally laminated on one surface of the back canvas. Then, at the time of manufacturing, first, both ends in the longitudinal direction of the band-shaped laminate are joined to each other such that no step is formed between the upper surface of the back canvas and the lower surface of the adhesive rubber sheet. Next, after the tubular laminate formed into a tubular shape by this butt joining is externally fitted to the forming drum with the back canvas facing the forming drum side, the core wire is spirally wound from above, and further, An adhesive rubber sheet made of an unvulcanized rubber sheet constituting the lower rubber portion of the adhesive rubber layer and the other belt components are sequentially wound around the core wire and vulcanized and formed. Thereafter, the vulcanized molded product is removed from the mold and cut into a predetermined width to obtain a power transmission belt.

According to a fifth aspect of the present invention, in the fourth aspect, the butt-joining of the band-shaped laminate is performed by sewing.

According to a sixth aspect of the present invention, in the fourth aspect, the butt-joining of the band-shaped laminate is performed by welding.

[0014]

According to the first to sixth aspects of the present invention, the back canvas has an unvulcanized rubber sheet comprising an unvulcanized rubber sheet constituting an upper rubber portion of an adhesive rubber layer with a core line as a boundary. With the belt, and the upper
Since both ends in the longitudinal direction together with the adhesive rubber sheet are butted against each other so that no step is formed on the upper surface of the rear canvas and the lower surface of the adhesive rubber sheet, and the seam or the seam is welded, the adhesive rubber sheet is formed at the time of molding. There is no misalignment due to the step in the core wire that comes into contact with the core wire, and the core wire is buried in the normal position in the adhesive rubber layer of the vulcanized power transmission belt without being displaced in the vertical direction. During use, the power transmission belt runs smoothly, and no abnormal vibration or noise occurs in the power transmission belt.

Further, since the rear canvas is butt-joined in a state of a thick material laminated with the adhesive rubber sheet, it is easy to perform butt-joining as compared with the case of butt-joining as a thin material alone, and there is abnormal vibration or abnormal vibration. A transmission belt that does not generate sound can be easily obtained.

[0016]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 shows a V-ribbed belt A as a transmission belt according to an embodiment of the present invention.
Reference numerals 2,... Denote an adhesive rubber layer embedded in the longitudinal direction of the belt, and an upper surface of the adhesive rubber layer 1 is integrally coated with a back canvas 3 and three rib rubber layers 4,
4 and 4 are provided integrally so as to extend in the longitudinal direction of the belt, and these constitute a V-ribbed belt A.

As will be apparent from the manufacturing method described below, the back canvas 3 is characterized in that the unvulcanized rubber sheet constituting the upper rubber portion 1a of the adhesive rubber layer 1 with the core wire 2 as a boundary. With the adhesive rubber sheet 1'a made of
Laminated on the strip, the adhesive longitudinal end with a rubber sheet 1'a are abutted to each other so as not to cause a step in the top fabric 3 top and the adhesion rubber sheet 1'a underside cylinder in this state of the strip laminate Are joined together. That is,
The back canvas 3 is integrally laminated with the adhesive rubber sheet 1 ′ a made of an unvulcanized rubber sheet constituting the upper rubber portion 1 a of the adhesive rubber layer 1 with the core wire 2 as a boundary, and (See FIG. 2). When the band-shaped laminate 5 is formed, the rear canvas 3 and the adhesive rubber sheet 1'a constituting the belt-shaped laminate 5 are joined to each other in a cylindrical shape by abutting the longitudinal ends of the rear canvas 3 and the adhesive rubber sheet 1'a. A step is not formed on the lower surface of 1'a. The butt joint may be performed by, for example, sewing with an overlock sewing machine, or may be performed by welding in which heat is applied to the butt portion in a state where both ends of the adhesive rubber sheet 1 ′ abut. The butt joints are indicated by reference numeral J. In FIG. 1, this butt joining is a so-called oblique butt joining in which the butt joining is performed obliquely with respect to the longitudinal direction of the belt. However, the butt joining may be performed by joining at right angles to the longitudinal direction of the belt. Formed into a cylinder by butt-joining
The above-mentioned core wire 2 is wound around the cylindrical laminate 5 ′ thus formed.
It is. After the core wire 2 is wound, the adhesive rubber
From the unvulcanized rubber sheet constituting the lower rubber portion 1b of the layer 1
Adhesive rubber layer covered with an adhesive rubber sheet 1'b
1 buried.

The core wire 2 is formed, for example, by twisting fibers of polyester, polyamide, aramid, glass or the like, forming an appropriate cord according to the use of the belt, and subjecting it to a heat stretching treatment and an adhesive treatment. Things.

At the time of manufacture, the adhesive rubber layer 1 is made of an unvulcanized rubber sheet 1a, 1b.
(See FIG. 5), and the unvulcanized rubber constituting these sheets is, for example, chloroprene rubber (CR), styrene butadiene rubber (SBR), nitrile rubber (NB)
R), natural rubber (NR), or a rubber elastic body composed of a blended rubber in which an additive is appropriately added to the blended rubber according to the use of the belt. The thickness of the adhesive rubber sheet 1'a constituting the upper rubber portion 1a may be set to, for example, 0.4 to 0.6 mm, but is not limited to this. What is necessary is just to set in consideration of nature. The method of laminating the adhesive rubber sheet 1'a on the rear canvas 3 is, for example, a method of laminating the rear canvas 3 and the adhesive rubber sheet 1 between a pair of calender rolls 6,6.
'A can be performed by topping or the like (FIG. 2
reference).

The back canvas 3 is formed by weaving, for example, a cotton thread or a nylon thread, and may be a commonly used canvas for a power transmission belt.

The rib rubber layer 4 may be made of the same material rubber as the adhesive rubber layer 1.

Next, the manufacturing procedure of the V-ribbed belt A configured as described above will be described.

First, an adhesive rubber sheet 1 ′ a composed of an unvulcanized rubber sheet constituting the upper rubber portion 1 a of the adhesive rubber layer 1 with the core wire 2 as a boundary is laminated on one surface of the back canvas 3. Prepare 5 As shown in FIG. 2, the band-like laminate 5 is formed by passing the back canvas 3 and the adhesive rubber sheet 1 ′ a between the pair of calender rolls 6, 6 so as to be pressed by the calender rolls 6, 6. To form a strip .

Next, as shown in FIG. 3, the belt-shaped laminate 5 is bias-cut so that the warp and the weft of the back canvas 3 are oriented at a predetermined angle with respect to the longitudinal direction of the belt. Are sequentially butt-joined by sewing with an overlock sewing machine or the like, and the belt-shaped laminate 5 is formed again. The butt joints are indicated by reference symbols J '.

Thereafter, both ends in the longitudinal direction of the back canvas 3 and the adhesive rubber sheet 1'a constituting the above-mentioned band-shaped laminated body 5 are separated from each other so that no step is formed between the upper surface of the back canvas 3 and the lower surface of the adhesive rubber sheet 1'a. Butts are joined by sewing with an overlock sewing machine or the like.

Thereafter, as shown in FIG. 4 and FIG. 5, the cylindrical laminate 5 formed into a cylindrical shape by this butt joining is formed.
′ Is externally fitted to the forming drum 7 with the back canvas 3 facing the cylindrical forming drum 7, and then the core 2 is spirally wound therefrom. After sequentially winding an adhesive rubber sheet 1 ′ b made of an unvulcanized rubber sheet constituting the lower rubber portion 1 b of the layer 1 and a rib rubber sheet 4 ′ as another belt component, the rib rubber layer 4 is shaped. A cylindrical sleeve 8 made of an elastic body such as rubber and having a concave and convex portion corresponding to a concave portion 8a and a convex portion 8b formed on the inner peripheral surface is externally fitted to the forming drum 7 and vulcanized.

Thereafter, the obtained cylindrical vulcanized molded article 9 is demolded and cut to a predetermined width, so that a plurality of cords 2, 2,... V-ribbed belt in which a back canvas 3 is integrally attached to an upper surface of an adhesive rubber layer 1 buried in a direction, and three rib rubber layers 4, 4, 4 are integrally provided on a lower surface to extend in a belt longitudinal direction. Get A. The butt joint J of the canvas material constituting the back canvas 3 of the V-ribbed belt A has a flat surface without any level difference. The adhesive rubber sheet 1'a constituting the lower layer of the band-shaped laminate 5 is integrally formed with the adhesive rubber sheet 1'b constituting the lower rubber portion 1b of the adhesive rubber layer 1 by vulcanization molding. One adhesive rubber layer 1 is formed.

The center position of the V-ribbed belt A formed as described above from the back of the belt is 1.0 design value.
For 5 mm, as shown in Table 1, 1.02 to 1.07 m
m. When abnormal vibration and abnormal noise due to the rear hanging of the V-ribbed belt A were confirmed together with Comparative Examples 1 and 2,
The results are shown in Table 1. Comparative Example 1 is a case where the back canvas 3 and the adhesive rubber sheet 1'a are both lap jointed, and Comparative Example 2 is a case where the adhesive rubber sheet 1'a is a lap joint and the rear canvas 3 is abutted. This is the case of joining.

[0030]

[Table 1]

As is clear from Table 1, in this embodiment, neither abnormal vibration nor abnormal noise was generated.
In Comparative Example 1, the position of the cord from the back of the belt is 1.30 to
The displacement was 1.40 mm, which was significantly larger in the vertical direction than in this example, and both abnormal vibration and abnormal noise were large. Comparative Example 2
Then, the center line position from the back of the belt is 1.10 to 1.20
mm, the amount of displacement in the vertical direction was smaller than that of the comparative example, but was still larger than that of the present example, and both abnormal vibration and abnormal noise were smaller than that of the comparative example 1, but larger than that of the present example.

The test for confirming abnormal noise was performed in the following manner.

<Confirmation Test of Abnormal Noise> As shown in FIG. 6, a V-ribbed belt A, which is a test piece, is wound around a driving pulley 11 and driven pulleys 12 and 13, and the idler 14 runs with a tension of 120 kgf. I let it. In this running state, a sound collecting microphone 15 is set near the idler 14 to be mounted on the back, and the sound collected by the sound collecting microphone 15 is collected by a sound level meter 16 and a recorder 17.
Was measured. The driving pulley 11 and the driven pulley 1
2 and 13 have the same size and a diameter of 100 mm, and the idler 14 has a diameter of 70 mm. The rotation speed of the driving pulley 11 is 1000 rpm.

As described above, in this embodiment, neither abnormal vibration nor abnormal noise was generated because the rear canvas 3 and the upper rubber portion 1a (adhesive rubber sheet 1'a) of the adhesive rubber layer 1 abut. In the joining, the butt joint portion J is flat and has no step. Therefore, when the core wire 2 is wound at the time of molding, the core wire 2 draws a perfect circle without being displaced in the vertical direction, and the V-ribbed belt A after molding is formed. This is due to the fact that it is properly positioned on the adhesive rubber layer 1 and smoothly passes through the idler 15 without generating abnormal noise without causing abnormal vibration.

On the other hand, in Comparative Example 1, the back canvas 3 and the upper rubber portion 1a of the adhesive rubber layer 1 (the adhesive rubber sheet 1a) were used.
'A) are lap joints, and in Comparative Example 2, the upper rubber portion 1a of the adhesive rubber layer 1 (adhesive rubber sheet 1'a)
Is a lap joint, and the joining portion is not flat, and a step is formed. Therefore, when the core wire 2 is wound at the time of molding, the core wire 2 is displaced in the vertical direction and does not draw a perfect circle, This is because the V-ribbed belt A cannot be properly positioned on the adhesive rubber layer 2 of the formed V-ribbed belt A, and as a result, abnormal vibration occurs, generating abnormal noise and making it impossible to pass through the idler 15 smoothly.

In the present embodiment, the rear canvas 3 is butt-joined not alone but in a thick state together with the adhesive rubber sheet 1'a. Butt joining can be performed more easily than in the case, and a V-ribbed belt A free of abnormal vibration and abnormal noise can be easily obtained.

In the above-described embodiment, the case where the transmission belt is the V-ribbed belt A has been described. However, any type of transmission belt can be used as long as the rear canvas 3 is provided on the back of the belt such as the V belt.

[0038]

As described above, according to the first to sixth aspects of the present invention, each of the back canvas is laminated in a strip shape with the adhesive rubber sheet constituting the upper rubber portion of the adhesive rubber layer. The suturing comb is butt-joined by welding so that there is no step at both ends, so the core wire can be buried in the proper position without being displaced up and down in the adhesive rubber layer of the transmission belt. The belt can smoothly run without generating abnormal vibration or abnormal noise. Furthermore, since the rear canvas is joined with the adhesive rubber sheet and joined in a thick state, the rear canvas can be butt-joined more easily than a single thin object, and abnormal vibration and abnormal noise can be prevented. A transmission belt that does not generate can be easily obtained.

[Brief description of the drawings]

FIG. 1 is a perspective view partially showing a V-ribbed belt.

FIG. 2 is a process diagram of topping an adhesive rubber sheet on a back canvas.

FIG. 3 is a plan view of a bias-cut band-shaped laminate.

FIG. 4 is a cross-sectional view showing the molding device immediately after the V-ribbed belt has been vulcanized.

FIG. 5 is a cross-sectional view taken along the line VV in FIG. 4 showing a state in which a belt component is set between a molding die and a sleeve.

FIG. 6 is a configuration diagram of a test device for confirming abnormal noise of a V-ribbed belt hung on the back.

FIG. 7 is a diagram corresponding to FIG. 4 in a state where the back canvas is overlapped.

FIG. 8 is a view corresponding to FIG. 4, showing a state in which an adhesive rubber sheet is overlapped and spliced.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Adhesive rubber layer 1a Upper rubber part of adhesive rubber layer 1'a Adhesive rubber sheet 1b Upper rubber part of adhesive rubber layer 1'b Adhesive rubber sheet 2 Core wire 3 Back canvas 4 'Rib rubber sheet (other belt configuration) 5) Belt-shaped laminate 5 'Cylindrical laminate 7 Molding drum 9 Vulcanized molded body A V-ribbed belt (transmission belt)

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI B29K 105: 24 (56) References JP-A-3-129146 (JP, A) JP-A-4-151048 (JP, A) JP-A-3-227851 (JP, A) JP-A-2-3724 (JP, A) JP-A-6-323368 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) F16G 1 / 00-5/20 B29D 29/00-29/10

Claims (6)

(57) [Claims] 1. A core wire is provided with an adhesive rubber layer embedded in the belt longitudinal direction, top fabric on the upper surface of the adhesive rubber layer is a transmission belt that is deposited, the top fabric is the core wire The belt is laminated integrally with the adhesive rubber sheet made of the unvulcanized rubber sheet constituting the upper rubber portion of the adhesive rubber layer at the boundary, and the upper part is formed in the state of this band-shaped laminate.
Serial longitudinal ends with adhesive rubber sheet is bonded to the tubular shape abut each other such that no step occurs at top fabric top and the adhesion rubber sheet lower surface, the cord is formed into a cylindrical shape by the butt joint
Rolled around the cylindrical laminate
Consists of an unvulcanized rubber sheet that constitutes the lower rubber part of the rubber layer
A power transmission belt, which is covered with an adhesive rubber sheet and is embedded in the adhesive rubber layer . 2. A butt joint of the strip laminate, transmission belt of claim 1 Symbol mounting characterized in that it is made by sewing. 3. A butt joint of the strip laminate, transmission belt of claim 1 Symbol mounting characterized in that it is carried out by welding. 4. A core wire comprises a bonding rubber layer which is embedded in the belt longitudinal direction, top fabric on the upper surface of the adhesive rubber layer is a method for producing a power transmission belt that is deposited, the boundary of the core wire An adhesive rubber sheet comprising an unvulcanized rubber sheet constituting the upper rubber portion of the adhesive rubber layer is provided with a band-like laminate integrally laminated on one surface of the back canvas, and both ends in the longitudinal direction of the band-like laminate are backed. The upper surface of the canvas and the lower surface of the adhesive rubber sheet are butt-joined to each other so that no step is generated.Then, the cylindrical laminate formed by this butt-joining is formed with the rear canvas facing the forming drum. After being externally fitted to the forming drum, a core wire is spirally wound from above, and furthermore, an adhesive rubber sheet made of an unvulcanized rubber sheet constituting a lower rubber portion of the adhesive rubber layer with the core wire as a boundary, and the like. Belt components Vulcanized molded wrapped, then manufacturing method of the driving belt, characterized in that the vulcanized molded by demolding to obtain a transmission belt with a width cut to a predetermined width. 5. The butt joint of the strip laminate, a manufacturing method of the driving belt according to claim 4 Symbol mounting characterized in that it is made by sewing. 6. A butt joint of the strip laminate, a manufacturing method of the driving belt according to claim 4 Symbol mounting characterized in that it is carried out by welding.